Number of ways to choose k items from n items without repetition and with order.
tfm.optimization.math.perm(
n, k, /
)
Evaluates to n! / (n - k)! when k <= n and evaluates to zero when k > n.
If k is not specified or is None, then k defaults to n and the function returns n!.
Raises TypeError if either of the arguments are not integers. Raises ValueError if either of the arguments are negative.